苇浆双塔氧脱木素的生产实践

Production Practice of Oxygen Delignification of Reed Pulp with Two Upflow Towers

进行了苇浆两段氧脱木素的实验室小试,在小试基础上建设了150t/d的O/OHMP漂白生产线。生产实践表明,苇浆卡伯值平均下降50%以上,漂后白度85%ISO以上,纸浆裂断长达到4.0km以上,氧脱木素废水送碱回收系统,M段和P段废水可实现全循环回用,H段废水排放量仅为30m3左右。与CEH漂白相比,废水排放量和排放的污染负荷减少70%以上,废水中AOX量下降约80%。

Based on the laboratory study of two stages oxygen delignification of reed pulp, a 150 t/d production line with O/OHMP bleaching sequence was built. The practice showed that the oxygen delignification with two up-flow towers is feasible and successful; kappa number reduces by over 50% after oxygen delignification with two up-flow towers; and the brightness and the breaking length of the pulp are respectively over 85%ISO and 4000m after O/OHMP bleaching; the filtrate of oxygen delignification is sent to alkali recovery system; M and P filtrates are recycled by countercurrent washing; only about 30m3 of H filtrate is discharged. Comparing with CEH bleaching, wastewater and pollution load discharges reduce by 70%, and AOX reduces about 80%.